update version checks to use command -v and add llm check

Use `command -v` instead of `/usr/bin/env` for consistency and reliability, and add check for `llm` command.

,

@@ -11,6 +11,8 @@ echo "PATH:" $(echo "$PATH" | tr ':' '\n' | wc -l) "paths [Please run ',path' to
 
 echo ""
 
-echo "Ruby version:" $(/usr/bin/env ruby -v)
-echo "Python version:" $(/usr/bin/env python --version)
+echo "Ruby:" $(command -v ruby || echo "not found")
+echo "Python:" $(command -v python || echo "not found")
+
+echo "llm:" $(command -v llm || echo "not found")